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buyModerate cluster of 3

Mark Campbell Winmill bought $84k of SELF

President and CEO at Global Self Storage, Inc.. 16,400 shares at an average of $5.12, traded Dec 3, 2025, filed Dec 5, 2025.

Conviction score
52
Value
$84k
16,400 shares
Holdings after
339,238
+5% from before
From 52-week low
+10%
low $4.41, close $4.86
From 52-week high
-8%
high $5.29, as of Dec 3, 2025

Score components

  • Role
    CEO
    +25
  • Trade size
    $84k at market
    +9
  • Relative to holdings
    Holdings up 5%
    +3
  • Price context
    Near the top of the 52-week range
    0
  • Cluster
    3 insiders buying within 14 days
    +15
  • Repeat buying
    First buy in 90 days
    0
  • Track record
    Too few past buys to judge (0 with prices)
    0

What happened after comparable buys

Same side and tier, against the S&P 500, at 1, 3 and 6 months. Shown to Pro users; the whole table is on the backtest page.

This signal so far: 1m +3.7%, 3m +4.5%, 6m +4.6%.

Price around the trade, and since

From a quarter before the trade to today. The arrow is the trade, the circle the day the filing reached EDGAR, which is the first day anyone outside could act; the dotted line is the S&P 500 rebased to that day's close.

SELFOct 9, 2026 · close 4.90
Since filing Dec 5, 2025: +4.0%SPY +14.7% · excess -10.6%

Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value; the dashed line is the close on the filing day, the dotted line SPY rebased to it.Charts by TradingView Lightweight Charts™

Rows in this filing

Every transaction in Form 4 0001019264-25-000003, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
Dec 3, 2025POpen-market purchase
Common Stock
+6,000$5.13$31k328,838Dec 5, 2025
Dec 4, 2025POpen-market purchase
Common Stock
+6,000$5.14$31k334,838Dec 5, 2025
Dec 5, 2025POpen-market purchase
Common Stock
+800$5.05$4,040335,638Dec 5, 2025
Dec 5, 2025POpen-market purchase
Common Stock
+3,600$5.09$18k339,238Dec 5, 2025

Related signals

Other insiders at Global Self Storage, Inc. and this insider’s other filings.

ScoreCompanyInsiderValueHoldingsFiled
25Weak
SELFbuy
Global Self Storage, Inc.
Mark Campbell Winmill
President and CEO
$21k
4,000 shares
+1%
28Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$86k
15,308 shares
+7%
28Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$84k
15,139 shares
+8%
27Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$75k
13,778 shares
+7%
27Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$68k
12,853 shares
+7%
23Weak
SELFbuy 2
Global Self Storage, Inc.
Russell E Burke III
director
$8,459
1,625 shares
+4%
26Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$61k
11,658 shares
+7%
32Weak
SELFbuy 2
Global Self Storage, Inc.
Winmill & Co. Inc
other
$63k
12,135 shares
+8%
25Weak
SELFbuy
Global Self Storage, Inc.
Mark Campbell Winmill
President and CEO
$21k
4,000 shares
+1%
35Weak
SELFbuy 3
Global Self Storage, Inc.
Donald Klimoski II
General Counsel
$2,252
446 shares
+1%

Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.

Mark Campbell Winmill bought $84k of SELF | InsiderTell